Tetramethylammonium (TMA) aluminosilicate is an important raw material for molecular sieve preparations. The soluble aluminosilicate salts of the quaternary ammonium cations, TMA in particular, are useful reagents for the synthesis of ultra large pore M41S. They are important as alkali sources of aluminosilicate dispersed on a molecular scale.
While the basic chemical principles would suggest that their preparation should be trivial, in practice, the apparently obvious approaches, such as described in the book "High-Resolution Solid-State NMR of Silicates and Zeolites" by G. Engelhardt and D. Michel, (published by John Wiley & Sons, 1987) on pages 96-99, have either failed or turned out to be impractical and/or inconvenient. Synthesis of TMA aluminosilicate, as reported by D. Hoebbel, G. Garzo, K. Ujszaszi G. Engelhardt, B. Fahlke and A. Vargha in Z. Anorg. Allg. Chemie., Vol. 484, pp. 7-21 (1982), involves dissolution of Al in TMA hydroxide, which is cumbersome and lengthy and liberates explosive hydrogen gas. Freshly precipitated Al hydrous oxide can also be used, but it requires multiple washing-of the gelatinous precipitate.
Therefore, it is an object of the present invention to provide a convenient synthesis method for the preparation of TMA aluminosilicate. It is a further object of the present invention to provide a TMA aluminosilicate reagent for use in the synthesis of M4!S.